Label sheet and method of manufacturing the same

ABSTRACT

A label sheet comprises a substrate and an adhesive layer formed by applying an adhesive agent to a surface of the substrate, said adhesive layer being formed only on a limited area of the surface. With such an arrangement and if it is part of a larger label sheet or a multi-layer structure of label sheets, it can be stripped off easily from the remaining part. If perforations are formed in adhesive free areas, they do not produce any projections of the applied adhesive agent so that the final product can be handled with ease. Additionally, by forming an adhesive-repellent layer on the outer surface with an ink type adhesive-repellent agent, the overall manufacturing process can be simplified and the product is adapted to making by hand.

This application is a continuation of application Ser. No. 08/509,245,filed Jul. 31, 1995, now abandoned.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a label sheet comprising a substrate carryingan adhesive layer on a surface thereof and, more particularly, itrelates to a label sheet comprising a substrate carrying an adhesivelayer on a surface thereof and printed information on the other surfacethat serves as a separable side of the label sheet, wherein saidadhesive layer is formed only on a limited area of the surface and/or aparting layer is formed by application on the other surface in order toimprove the separability of the label sheet, the efficiency of formingperforations in the label sheet and the adaptability to marking by handof the separable side of the label sheet.

2. Background Art

A variety of label sheets are known to date and some of the popularapplications of label sheets include post cards, envelopes, paper slips,parcels and packaged goods in the fields of mail, delivery, distributionand retailing to list a few. A typical label sheet comprises a substratecarrying printed information in a given area of a surface thereof, whichinformation may be in the form of bar codes and represent the contentsof a parcel or package, if the label sheet is to be applied to theparcel or package, and a layer of a pressure-responsive adhesive agenton the other surface. Such a label sheet may additionally comprise anadhesive-repellent cover sheet typically treated with silicon so thatthe adhesive layer of the label sheet is covered and protected by thecover sheet and the label sheet can be brought to actual use bystripping off the cover sheet from the label sheet with ease or,alternatively, the printed information carrying surface of such a labelsheet may be directly treated with silicon to make it adhesive-repellentand operate as a cover sheet for the adhesive layer of another labelsheet so that no separate and independent cover sheet may additionallybe required. In either case, the label sheet may be part of a largerlabel sheet and can be separated from the remaining part by ripping itoff along perforations and stripping off the cover sheet or simplyremoving the label sheet from an underlying sheet before it is appliedto an object.

A known label sheet of the above described type will be described ingreater detail by referring to FIG. 19 of the accompanying drawing nthat shows a cross sectional view of a conventional label sheet. In FIG.19, a rectangular label sheet 91 comprises a substrate 92, an ink layer95 formed on a surface of the substrate 92 and carrying printedinformation therein, a separable cover layer 93 of an adhesive-repellentmaterial formed on the ink layer 95 to cover and protect the printedinformation and an adhesive layer 94 formed on the other surface of thesubstrate 92. A number of such label sheets are arranged vertically on aone on the other basis to form a multi-layer structure in such a waythat the separable cover layer 93 of a label sheet held in contact withthe adhesive layer 94 of another label sheet placed directly on it andso on. Such a multi-layer structure of label sheets may be part of alarger rolled or flat label sheet product or a larger comprising anumber of such multi-layer structures that are separable from each otheralong perforations. Thus, an individual label sheet can be separatedfrom the remaining part by ripping it off along perforations andstripping off the cover sheet before is applied to an object.

A conventional label sheet as described above is, however, accompaniedby a number of disadvantages. Firstly, since it carries an adhesive onthe entire surface of the substrate, it may require s considerableeffort for stripping it off from the underlying label sheet, although noparticular measures have hitherto been taken to solve this problem.Thus, an attempt to strip off a single label sheet from the remaininglabel sheets can often end up with unintentionally taking up a number oflabel sheets at a time. Secondly, in the process of producingperforations in a larger label sheet for defining the boundaries ofindividual label sheets by means of a perforator, the adhesive can stickto the perforator to reduce the level of precision with which theperforating operation is carried out and give rise to unevenlydistributed perforations, which by turn make the label sheets not easilyseparable and can result in deformed or damaged labels. Additionally,the larger label sheet and the perforator to which the adhesive issticking may catch and bite each other as the former is fed in and outto cause a trouble of jamming and consequently a reduced productivity.Still additionally, as the perforator needle cuts through the substrateand comes out of it to form a perforation there, the substrate may riseand project around the perforation mainly because of the existence ofthe adhesive around the perforation. The net result of such projectionswill be a deformed roll if the perforated label sheets are taken up toform a roll. Such a deformed roll may be not only disagreeable inappearance but also clumsy in the motion of being fed out if it isfitted to a printer or a label holder. If a number of label sheets arenot wound up to form a roll but stored as a stack, the adhesive can flowout from the lateral sides of the stack.

On the other hand, an adhesive-repellent agent is applied to the othersurface of the substrate of the label sheet to form anadhesive-repellent layer that covers the characters and/or patternsprinted on that surface. In other words, two different agents of theadhesive-repellent and the printing ink have to be used on theadhesive-repellent side of the label sheet, involving two separateprocessing steps, to make the overall label sheet rather thick andcostly and the entire manufacturing operation inefficient anduneconomic.

Adhesive-repellent agents used for conventional label sheets typicallycontain silicon by between 65 and 95% by weight. With such a highsilicon content, the surface of the adhesive-repellent layer in hardlyadapted to marking by means of a felt-tipped marker, a pencil or astamp. In other words, any additional information in the form ofcharacters and/or patterns recorded on the exposed surface of the labelsheet at the time when it is applied to an object can easily be wipedout by hand or some other thing that may happen to touch it by chance sothat any such attempt will find itself abortive.

Known adhesive-repellent cover sheets used for covering and protectingconventional label sheets have to be thrown out once they are peeled offfrom the respective label sheets to make waste because they have beentreated with silicon and hence not feasibly recycled. In an attempt todissolve this problem, there have been proposed a multi-layer structureof label sheets, where the adhesive layer sides of two verticallysuccessive label sheets are designed to be put together in such a waythat each of the two adhesive layer sides is divided into adhesive areasand adhesive-repellent areas and the adhesive areas of either one of thetwo adhesive layer sides exactly corresponds to the adhesive-repellentareas of the oppositely disposed adhesive layer side. This arrangementis free from the above identified problems so long as the two labelsheets are used at a same time. However, the two label sheets are notnecessarily used at a same time and, if either one is used before theother one, the adhesive layer side of the remaining one has to beprotected by some means so that it may not unintentionally stick to anobject, requiring the user to give particular care to it. While theunused adhesive layer side may conceivably be stored by folding it insuch a way that its adhesive areas respectively contact with thecorresponding adhesive-repellent areas, such a practice will not bepossible without exposing some of the adhesive areas. So there exists ademand for a label sheet of the category under consideration that is notaccompanied by the above problems.

SUMMARY OF THE INVENTION

In view of the above problems, it is an object of the present inventionto provide a label sheet comprising a substrate carrying on a surfacethereof an adhesive layer formed only on a limited area of the surfaceto leave an adhesive free area on the surface so that it may be easilyseparated from an underlaying label sheet. If the label sheet is part ofa larger label sheet from which it is separated by ripping it off alongboundary perforations when it is used, the perforations mayadvantageously be formed in an area that is free from any adhesive sothat no projections may be produced by the adhesive applied around theperforations.

Another object of the invention is provide a label sheet comprising asubstrate carrying an adhesive layer on a surface thereof and anink-made separable layer on the other surface, said ink containing anadhesive-repellent agent and a coloring agent. Characters and/orpatterns may advantageously be printed on the label sheet by means ofthe ink.

Still another object of the invention is to provide a label sheetcomprising a substrate carrying an adhesive layer on a surface thereofand an ink-made separable layer on the other surface, said inkcontaining an adhesive-repellent agent to a relatively low concentrationso that additional information in the form of characters and/or patternsmay be recorded on the separable layer and may not be wiped out byaccident when the label sheet is actually used. Still another object ofthe invention is to provide a method of manufacturing such a labelsheet.

A further object of the invention is to provide a label sheet comprisinga substrate carrying an adhesive-repellent layer within a limited areaand an information recording section in the remaining area of a surfacethereof and an adhesive layer within a limited area and an adhesive freesection in the remaining area of the other surface thereof, the area ofsaid information recording section exactly corresponding to that of theadhesive free section.

If the above label sheet is part of a multi-layer structure of a numberof such label sheets and has an adhesive free section and an adhesivelayer on a same surface thereof, said adhesive free section and saidadhesive layer dividing the surface into identical two halves, theadhesive free section may advantageously carry an adhesive-repellentlayer and be arranged in such a way that, if the label is folded along acenter line, the area of the adhesive layer is put to contact exactlywith the area of the adhesive-repellent layer and that the area of theadhesive layer on the underside of the label sheet exactly correspondsto the area of the adhesive-repellent layer of the upper side of anunderlying label sheet.

A label sheet according to the invention and having an adhesive freearea on the adhesive layer carrying side of the sheet can be easilystripped off from the remaining portion of a larger label sheetcomprising it as part thereof. If the perforations of the label sheetare formed in the adhesive free area, no projections may be produced bythe adhesive applied to the substrate to make the label sheet easy tohandle.

With a label sheet according to the invention and having an ink-madeseparable layer on a surface of the substrate, said ink containing anadhesive-repellent agent and a coloring agent, the coloring agent andthe adhesive-repellent agent can be applied simultaneously to producethe separable layer in a simplified manner.

With a label sheet according to the invention and having an ink-madeseparable layer on the other surface, said ink containing anadhesive-repellent agent to a relatively low concentration so thatadditional information in the form of characters and/or patterns may berecorded on the separable layer, the separable layer is highly adaptedto marking by means of a felt-tipped marker, a pencil or a stamp.Additionally, since a method of manufacturing a label sheet according tothe invention involves the use of an ink-type adhesive-repellent agentfor a separable layer, the separable layer may be formed on all or aselected area of a surface of the substrate by means of a conventionalprinting machine. If the ink-type adhesive-repellent agent is of anultraviolet-ray-set type, the separable layer may be dried quickly byirradiating it with ultraviolet rays.

With a label sheet according to the invention and having an informationrecording section formed on an adhesive-repellent layer carrying surfaceof the substrate and an adhesive free section on the other surface ofthe substrate, the information, recording section may not be subjectedto a stripping action so that it is more adapted for recordinginformation.

With a label sheet according to the invention and forming part of amulti-layer structure of a number of such label sheets, said label sheethaving an adhesive free section and an adhesive layer on a same surfacethereof, the adhesive free section carrying an adhesive-repellent layerand being arranged in such a way that, if the label is folded along acenter line, the area of the adhesive layer is put to contact exactlywith the area of the adhesive-repellent layer and that the area of theadhesive layer on the underside of the label sheet exactly correspondsto the area of the adhesive-repellent layer of the upper side of anunderlying label sheet, it may not stick to any objects if the overlyinglabel sheet has been stripped off. If the area of the adhesive-repellentlayer of each label sheet is exclusively used as a stub, it will make anexcellent stub that would not stick to any objects. Additionally, sincethe area of the adhesive layer of each label sheet carries an adhesivealong the opposite edges, it can be securely bonded to an object by theadhesive along the opposite edges.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross sectional side view of a multi-layer structure ofrectangular label sheets according to the invention.

FIG. 2 is a top view of an embodiment of label sheet according to theinvention.

FIG. 3 is a bottom view of the embodiment of FIG. 2.

FIG. 4 is a bottom view of another embodiment of label sheet accordingto the invention.

FIG. 5 is a bottom view of still another embodiment of label sheetaccording to the invention.

FIG. 6 is a perspective view of another multi-layer structure ofrectangular label sheets according to the invention and havingperforations for separating it into individual label sheets.

FIG. 7 in a schematic perspective view of a roll of rectangular labelsheets according to the invention.

FIG. 8 is a perspective partial view of the roll of rectangular labelsheets of FIG. 7.

FIG. 9 is a cross sectional view of the embodiment of FIG. 8 taken alongline A--A.

FIG. 10 is a cross sectional view of the embodiment of FIG. 8 takenalong line B--B.

FIG. 11 is a schematic perspective view of another roll of rectangularlabel sheets according to the invention.

FIGS. 12(a) and 12(b) are top and bottom views of a label sheetaccording to the invention, illustrating how they correspondgeometrically and functionally.

FIG. 13 is a perspective view of a package to which a label sheetaccording to the invention is applied.

FIG. 14 is a perspective view of an embodiment of overlap type labelsheet according to the invention.

FIG. 15 is a cross sectional view of another embodiment of overlap typelabel sheet according to the invention.

FIG. 16 is a cross sectional view of still another embodiment of overlaptype label sheet according to the invention.

FIG. 17 is a cross sectional view of a further embodiment of overlaptype label sheet according to the invention.

FIG. 18 is a schematic flow chart of a method of manufacturing a labelsheet according to the invention.

FIG. 19 is a cross sectional view of a conventional label sheet.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, the present invention will be described by referring to theaccompanying drawings that illustrate preferred embodiments of theinvention.

FIG. 1 is a cross sectional view of an embodiment of multi-layerstructure A of label sheets according to the invention. FIG. 2 is a topview of an embodiment of rectangular label sheet according to theinvention. FIG. 3 is bottom view of the embodiment FIG. 2, where anadhesive agent is applied to the entirely area to form an adhesive layerexcept a several millimeters wide adhesive free zone M that makes thelabel sheet to be easily separated from the multi-layer structure A witha finger tip. The label sheet 1 comprises a substrate 2 typically madeof paper, synthetic paper or synthetic film, a separable layer 3 of acolored or transparent adhesive-repellent agent formed on a surface ofthe substrate 2 and an adhesive layer 4 formed on the other surface ofthe substrate 2. The-adhesive layer 4 of the label sheet is placedsquarely on the separable layer 3 of an underlying label sheet and so onto form a multi-layer structure A, which is placed on theadhesive-repellent upper surface of a board 7 as shown in FIG. 1. Whilethe adhesive free zone M is formed at a corner of the label sheet inFIG. 3, it may alternatively be arranged along the entire length of anedge of the label sheet as shown in FIG. 4. Still alternatively, a pairof adhesive free zones may be arranged respectively along opposite edgesof the label sheet as shown in FIG. 5. The location and the size of theadhesive free zone may be determined as a function of the overall sizeand the profile of the label sheet 1.

FIG. 6 is a schematic perspective view of a multi-layer structure A oflabel sheets, each layer being separable from the underlying layer andhaving four rectangular label sheets 1 that may be separated from eachother along perforations 6. Although perforations are arranged to show ahorizontal line and a vertical line in FIG. 6, they may alternativelyarranged in a number of parallel rows. Each layer may comprise more thanfour label sheet. Preferably, each label sheet of each layer has anadhesive free section. Perforations are preferably formed along thecenter lines 6 of adhesive free sections. With this arrangement, noadhesive would stick to the perforator tip coming out of the multi-layerstructure during the perforating operation and the adhesive free sectionof each label sheet provides a lug for separating the label sheet.

Now, a roll of label sheets according to the invention will be describedby referring to FIGS. 7 through 10.

FIG. 7 is a schematic perspective view of a roll of label sheets andFIG. 8 is a perspective partial view of the roll of rectangular labelsheets of FIG. 7. FIGS. 9 and 10 are cross sectional views of theembodiment of FIG. 8 taken along lines A--A and B--B respectively.

Assume that the label sheets 11 of the above embodiment are those usedfor delivering products to customers. A substrate 12 that is common toall the label sheets of the roll carries a (separable) layer 14 of asilicon-type adhesive-repellent agent on the outer surface thereof and ablank form K is printed on the surface of the separable layer 14 so thatthe name, the specifications and the number of the products to which thelabel is attached may be entered by hand writing or by means of a stamp.The substrate 12 also carries on the inner surface thereof a (adhesive)layer 13 of a pressure responsive adhesive agent that is divided intounit sections by adhesive free sections 16 arranged at regularintervals. A line of perforations 17 is formed along the center line ofeach adhesive free section 16 so that no adhesive would stick to theperforator tip coming out of the multi-layer structure during theperforating operation to improve the level of precision with which theperforations are formed. Additionally, since no adhesive agent existsaround the perforations, no projections would be formed around them. Theadhesive free sections 16 provide lugs for separating the respectivelabel sheets.

Materials that can be used as adhesive-repellent agents for the purposeof the invention include water soluble silicon oil, silicon oilemulsion, silicon rubber emulsion and other silicon type water solublerepellent agents as well as water-repellent agents containing a Warnertype chromium complex salt and water soluble polyethylene imine typenon-silicon repellent agents. Ink type repellent agents containingrepellent substances such silicon and/or wax may also be used. Unlikethe above embodiment, the separable layer may not necessarily cover theentire outer surface of a label sheet according to the invention and itmay alternatively be formed only in part thereof in such a way that itexactly correspond to the adhesive layer on the other side of the labelsheet. An anti-adhesive-repellent agent is typically applied between thesubstrate and the adhesive-repellent agent. In other words, theseparable layer 14 on the surface of a label sheet according to theinvention normally comprises a layer of an anti-adhesive-repellent agentalso such a layer is not necessarily required for the purpose of theinvention.

Any ordinary adhesive agents and adhesive agents that allow separationand readhesion may be used for the purpose of the invention. Thecombination of an adhesive-repellent agent and an adhesive agent and therates at which they are respectively applied depend on the applicationof the label, the material of the label substrate, the environment ofthe applied label and other considerations. The separable layer may beomitted depending on the adhesion of the adhesive agent.

Any paper including ordinary quality paper, coated paper and othersynthetic paper may be used for the label substrate if such paper isfeasibly used with adhesive-repellent agents, adhesive agents and inktype adhesive-repellent agents selected for the purpose of theinvention.

Adhesive free sections 16 also extend along the longitudinal edges ofthe label sheets 11 of the above embodiment. These sections may beadvantageous when a wide roll of label sheets is firstly prepared andthen cut into a plurality of unit rolls because the cutter would remainfree of the adhesive agent and the latter would not flow out of thelateral sides of the roll during storage.

An ink type adhesive-repellent agent is preferably used for the aboveembodiment. Ink type adhesive-repellent agents that can be used for thepurpose of the invention are those containing a properadhesive-repellent agent by a concentration lower than that or aconventional ink type adhesive-repellent agent or less than 85 to 95% byweight. An ink type adhesive-repellent agent contains as principalingredients a vehicle, a coloring agent, an adhesive-repellent agent anda promoter agent. The vehicle contains a drying oil, a synthetic resin,a solvent and a plasticizer. Materials that can be used for the vehiclemay be those that can be used for ultraviolet-ray-set type ink andinclude oligomers such as polyesateracrylate, epoxyacrylate,urethaneacrylate, polyoleacrylate, reactive diluents, monofunctionalmonomers such as photopolymerizable monomers, polyfunctional monomersand photopolymerization initiators. The vehicle is preferably anultraviolet-ray-set type repellent overprint varnish containing acrylicacid ester resin as a principal ingredient. The vehicle is applied tothe outer surface of the label sheet substrate and then made to set byirradiating ultraviolet rays to produce a layer. The coloring agent maybe an organic or inorganic pigment. The promoter agent may be a dryingagent or compound.

These ingredients are mixed to a ratio where the adhesive-repellentagent occupies 5 to 30% by weight of the entire mixture. If the contentof the adhesive-repellent agent is less than 10% by weight, the productwould not show any adhesive-repellent property so that the adhesivelayer and the separable layer would be firmly-bonded together to makethe product total useless. If, on the other hand, the content of theadhesive-repellent agent is greater than 35% by weight, the mixturehardly operates as ink and no marking would become possible by means ofsuch a mixture. Preferably the content of the adhesive-repellent agentis between 15 and 25% by weight and more preferably it is between 18 and22% by weight. A recommendable mixing ratio of the vehicle, the coloringagent, the adhesive-repellent agent and the promoter agent would be 70%,10%, 15% and 5% by weight respectively. With such a ratio, the mixturewill operate both as ink and as an adhesive-repellent agent so that theoverall thickness and the manufacturing cost of the label sheet would besignificantly reduced.

As the ink type adhesive-repellent agent of a label sheet according tothe invention contains less silicon than a conventionaladhesive-repellent agent, its adhesive-repelling effect is slightlylower than that of the conventional agent, although this advantage canbe compensated by selecting appropriate rates for applying theadhesive-repellent agent and/or the adhesive agent. More specifically,the adhesive-repellent agent may be applied at a rate higher than thatof the conventional agent. Alternatively or simultaneously, the rate ofapplication of the adhesive agent may be reduced without adverselyaffecting the adhesion of the agent because of the fact that it istypically of an acryl or rubber type. Thus, the problem of a loweradhesive-repelling effect of a label sheet according to the inventioncan be dissolved with ease by selecting appropriate rate for applyingthe adhesive-repellent agent and/or the adhesive agent.

For the purpose of the invention, the ink type adhesive-repellent agentmay be applied to the entire outer surface or a selected area of theouter surface of the substrate of a label sheet. If it is applied onlyto a selected area, a conventional adhesive-repellent agent may beapplied to the remaining surface area. There is no specific limit forthe size of the selected area and the size may be determined dependingon the application of the label sheet. Alternatively, a conventionaladhesive-repellent agent may be applied to the entire outer surface ofthe substrate of a label sheet and the ink type adhesive-repellent agentmay be applied to a selected area of the surface of the layer of theconventional adhesive-repellent agent.

The separable layer 3 or 14 may be formed by printing the entire surfaceof the outer surface of the label sheet 2 of 12 with an ink typeadhesive-repellent agent or by printing a pattern and/or characters witha color ink type adhesive-repellent agent on the outer surface and thencoating the pattern and/or characters with a transparent ink typeadhesive-repellent agent so that the outer surface of the substrate ofthe label sheet 2 or 12 may carry a plurality of ink layers.

Now, the relationship between the adhesion of a label sheet according tothe invention and the unwinding force required to feed forward a roll oflabel sheets according to the invention. In an experiment, coated paperand quality paper were used for the substrate and an ink typeadhesive-repellent agent layer was formed on the outer surface of thesubstrate by applying an ultraviolet-ray-set type repellent overprintvarnish (UP200-trade name: available from T&K TOKA Co., Ltd.) comprisingas a principal ingredient acrylic acid ester that contained silicon by20% by weight at a rate of 1.5 g/m² by means of a resin printing blockto prepare a roll of label sheets. The unit label sheets were defined byperforations and an acryl type adhesive agent was applied at a rat of10.0 g/m² to the entire inner surface of the substrate except areassurrounding the perforations to produce an adhesive layer.

The prepared roll of label sheets was used by unwinding the roll andripping off the front end label sheet from the roll so that it was readyto be applied to a packaged product.

The force required to unwind the roll at a low rate and separate thefront end label sheet from the roll (as define by JIS-Z0237; A low valuerepresents easy separation.) and the adhesion per unit length of eachunit label sheet when applied to a stainless steel plate (as defined byJIS-Z0237; a higher value represents strong adhesion.) were measured.Table 1 below shows the results of the experiment.

                                      TABLE 1                                     __________________________________________________________________________             Adhesive                                                                            Adhesive-                                                                            Adhesion                                                                           Low Speed                                             Label Agent Appl. repellent Appl. (A) Unwinding Force                        No. Substrate Rate (g/m.sup.2) Rate (g/m.sup.2) (g/25 mm) (g/25 mm)         __________________________________________________________________________                                       A/B                                        1  coated paper                                                                        10.0  1.5    131  18      7.3                                          2 " 10.5 2.5 180 58 3.2                                                       3 " 10.5 2.5 199 55 3.6                                                       4 " 11.0 2.0 243 39 6.2                                                       5 " 11.5 2.0 257 31 8.3                                                       6 " 12.5 2.5 299 45 6.6                                                       7 " 14.0 2.5 313 56 5.6                                                       8 " 15.0 3.0 451 60 7.5                                                       9 quality paper 12.0 1.0 216 122  1.8                                         10 " 13.5 2.5 310 90 3.4                                                      11 " 14.0 2.5 360 96 3.8                                                    average of coat.                                                                       12.0  2.3    269  45      5.8                                          pa.                                                                           average of 13.0 2.0 295 103  2.9                                              qual. pa.                                                                     conventional -- -- 300 50˜80 6-3.8                                      paper                                                                       __________________________________________________________________________

As shown In Table 1 above, the force required to unwind a unit labelsheet from the roll of label sheets was about 103 g/ 25 mm of width inaverage if quality paper was used for the label substrate, whereas thevalue for a roll of comparable conventional label sheets was about 80g/25 mm of width, meaning that a label sheet according to the inventionmay require a slightly greater force as compared with a conventionalone, although the former did not provide any problems such as bonding ofthe bonded separable layer and the adhesive layer in practicalapplications. With a label sheet according to the invention and usingsynthetic paper for the label substrate, the force required to unwind itwas 45 g/25 mm of width in average, whereas the value for a roll ofcomparable conventional label sheets was about 50/25 mm of width toprove that the both were undiscriminable in practical applications.

The adhesion of each unit label sheet having a width of 25 mm was testedby applying it to a stainless steel plate and stripping it off from theplate after five minutes with an instrument similar to the one used fordetermining the force for unwinding each label sheet. As a result of theexperiment, it was found that the average adhesion was 295 g/25 mm ofwidth for label sheets using quality paper for the substrate and 259/25mm of width for those using coated for the substrate. While these valueswere slightly lower than the average of comparable conventional labelsheets, which was about 300 g/25 mm of width, the differences areinsignificant and the specimens did provide any problem in practicalapplications.

All the specimens in the table were good for marking by hand or by meansof a stamp and felt-tipped markers can be used with them. The ratios ofthe adhesion and the low speed unwinding force is closely related to theadaptability of the specimens to marking by hand and by means of astamp. More specifically, a high ratio of the adhesion to the low speedunwinding force represents a high separability and a poor adaptabilityto marking. For example, if the ratio of the adhesion to the low speedunwinding force of a specimen is less than 1.5, it shows an excellentadaptability to marking and a poor separability. If, to the contrary,the ratio exceeds 8.5, the specimen would not show any adaptability tomarking although it has an excellent separability. Thus, the ratio ofthe adhesion and the low speed unwinding force needs to be found between1.5 and 8.5, preferably between 2.5 and 7.5 and more preferably between3 and 7.

Now, another embodiment of the present invention will be described byreferring to FIGS. 11 through 13. FIG. 11 shows a roll of strip-shapedlabel sheets 21 comprising a substrate 22 typically made of a roll ofpaper that carries on the outer surface printed characters and patterns27 and blank areas 23 and adhesive-repellent sections 24. The roll isalso provided with lines of perforations 25 arranged at regularintervals to define individual unit label sheets. More specifically, asshown in FIG. 12(a), the blank areas 23 are located along the centerline of the substrate 22 and flanked with a pair of lateraladhesive-repellent sections 24. Each unit label sheet carries a set ofcharacters and a pattern 27 that are arranged appropriately by printingon the outer surface thereof regardless of the locations of the blankarea 23 and the adhesive-repellent sections 24. FIG. 12(b) shows theinner surface of the substrate 22, which carries longitudinal adhesivesections in areas exactly correspond to the adhesive-repellent sectionson the outer surface of the substrate 22.

As the substrate 22 is wound to form a roll with the outer surfaceexposed to the atmosphere, the adhesive sections 26 come to be held incontact with and covered by respective adhesive-repellent sections 24.When feeding out the roll of label sheets, the adhesive sections 26 willeasily be separated from the corresponding adhesive-repellent sections24 by simply pulling the front end of the roll 80 that no particulareffort will be required for unwinding the roll. As the front end labelsheet 21 in ripped off from roll along the line of perforations 25defining its boundary, it becomes ready to be applied to the package ofa product by way of the adhesive sections 26 on the back side of thelabel sheet 21 and characters and patterns may be marked on the blankarea 23 of the label sheet regardless. If the substrate is made of amaterial that can pass the ink applied to the blank area 23 throughitself until the ink can contaminate the package and the product insidethe package or the adhesive agent applied to the back side of the labelsheet can pass through the substrate 22 to come to the surface and loseits proper adhesion, a filling material may be applied to the innersurface of the substrate 22 in advance. Alternatively, the lateraladhesive sections 26 may be arrange of the lateral edges of thesubstrate 22 so that no adhesive agent would flow out of the lateralsides of the roll. The adhesive sections 26 may not necessarily beformed as continuous strips and may alternatively be realized in theform of a number of spots. With the above embodiment of roll of labelsheets, the front end label sheet 21 is ripped off from the roll alongthe boundary line of perforations 25 and any necessary additionalinformation such as the name and the address of the receptor of thepackage is entered into the blank area and then applied to the packageby means of the adhesive sections 26 of the back aide of the label sheet21 as shown in FIG. 13.

A still other embodiments of the invention will be described byreferring to FIGS. 14 through 17. FIG. 14 is a sectional view of a firstone of the embodiments and FIG. 15 is a sectional view of a second oneof the embodiments, whereas FIGS. 16 and 17 respectively show third andforth ones of the embodiments in cross section.

Referring to FIG. 14, the embodiment is an overlap type label sheet 31comprising an upper label sheet 32 and a lower label sheet 32, of whichthe upper label sheet 32 can be separated into an adhesive slip 35 and astub 36 along a line of perforations 34. The adhesive slip 35 isdesigned as a label of a product and carries on the outer surfacethereof information 37 concerning the product including the name, theproduct number and the specifications of the product in printedcharacters. Likewise, the stub 36 also carries on the outer surfacethere information 38 concerning the product. The lower label sheet 33has a configuration same as that of the upper label sheet 32 and can beseparated into an adhesive slip 40 and a stub 41 along a line ofperforations 49.

The adhesive slip 35 of the upper label sheet 32 carries on the backside thereof strip-shaped adhesive areas 42a, 42b, 42c formed byapplying a strong adhesive agent such as an acrylic two solutioncross-linking type adhesive and strip-shaped adhesive-repellent areas43a, 43b formed by applying silicon, said adhesive areas and saidadhesive-repellent areas being arranged in an alternating manner. On theother hand, the stub 36 of the upper label sheet 32 carries on the backside thereof an adhesive-repellent area 43c covering the entire surfaceof the back side. The adhesive areas 42a, 42b, 42c and theadhesive-repellent areas 43a, 43b, 43c are arranged in such a way that,when the upper label sheet 32 is folded along the center line or theseparating the adhesive area 42b and the adhesive-repellent area 43b,the adhesive are 42a, 42c and 42b respectively come into contact withthe adhesive-repellent areas 43a, 43c and 43b. The adhesive areas 42cand 42a of the adhesive slip 35 are respectively located at the edgesclose to and remote from the stub 36.

On the other hand, the lower label sheet 33 has a configuration same asthat of the upper label sheet 32 and carries on the back side thereofstrip-shaped adhesive areas 42a, 42b, 42c formed by applying a strongadhesive agent such as an acrylic two solution cross-linking typeadhesive and strip-shaped adhesive-repellent areas 43a, 43b formed byapplying silicon. The upper and lower label sheets 32 and 33 are puttogether so that the adhesive areas 42a, 42c and 42b are respectivelyheld in contact with the adhesive-repellent areas 43c, 43a and 43b.

With the above arrangement, the adhesive areas 42a, 42b and 42c of eachof the overlap type label sheets 32 and 33 are constantly covered andprotected respectively by the corresponding adhesive-repellent areas43a, 43b and 43c so that the use of particularly prepared cover sheetsis not required. To use the overlap type label sheet 31, the upper labelsheet 32 is stripped off from the lower label sheet 33 and then the stub36 is ripped off from the adhesive slip 35 along the perforations 34.Thereafter, the adhesive slip 35 is applied to the package (not shown)containing a right product represented by the information 37 on thesurface by way of the exposed adhesive areas 42a, 42b and 42c. Since theback side of the stub 36 is totally occupied by the adhesive-repellentarea 43c, it can be handled without difficulty, while the adhesive slip35 firmly sticks to the package by way of the two lateral adhesive areas42a and 42c and would not accidentally come off from the package.

The lower label sheet 33 that is left unused can be stored by folding itinto two halves along the center line thereof or the boundary line ofthe adhesive 42b and the adhesive-repellent area 43b so that theadhesive areas 42a, 43a and 43b comes into contact with theadhesive-repellent areas 43c, 43a and 43b respectively. Under thiscondition, the folded lower label sheet 33, the adhesive areas 42a, 42band 42c are covered and would not accidentally stick to any object.Additionally, since the adhesive areas can be easily peeled off from thecover, the label sheet becomes ready for use any time.

Now, the second embodiment will be described by referring to FIG. 15.This embodiment of overlap type label sheet differs from the firstembodiment only in that the adhesive areas 57a, 57b and 57c and theadhesive-repellent areas 56a, 56b and 56c of this embodiment arearranged differently from their counterparts of the first embodiment.More specifically, not only the adhesive areas 57a and 57b but also theadhesive-repellent area 56c on the back side of each of the adhesiveslips 56 and 59 of the upper and lower label sheets 52 and 53 arecontained within a portion that corresponds to each of theadhesive-repellent areas 56a on the back side of the stubs 54 end 55.Otherwise, the embodiment is exactly same as the above described firstembodiment and therefore would not be described here any further. Notthat each of the label sheets 52 and 53 can be folded into two halvesalong the center line or the boundary line of the adhesive area 57c andthe adhesive-repellent area 56b.

The third embodiment will then be described by referring to FIG. 16.This embodiment of overlap type label sheet differs from the abovedescribed first embodiment only in that the adhesive areas 67a, 67b and67c and the adhesive-repellent areas 66a, 66b and 66c of this embodimentare arranged differently from their counterparts of the firstembodiment. More specifically, the adhesive-repellent areas 65b, 65barranged on the back sides of the respective adhesive lips 66, 67 of theupper and lower label sheets 62 and 63 partly contact with each other.With this arrangement, each of the label sheets 62 and 63 can be foldedinto two halves along an imaginary line passing through of theadhesive-repellent area 65b arranged at the middle of the label sheet 62or 63.

Finally, the fourth embodiment will be described by referring to FIG.17. This embodiment of overlap type label sheet differs form the abovedescribed first embodiment only in that the adhesive areas 74a, 74b and74c and the adhesive-repellent areas 75a, 75b and 75c of this embodimentare arranged differently from their counterparts of the firstembodiment. More specifically, the adhesive-repellent area 75c arrangedon the back side of each of the stubs 78, 79 of the upper and lowerlabel sheets 72 and 73 is extended into the adjacent adhesive slip 76 or77 and not only the adhesive areas 74a and 75b but also theadhesive-repellent area 75a on the back side of each of the adhesiveslips 76 and 77 of the upper and lower label sheets 72 and 73 arecontained within a portion that corresponds to each of theadhesive-repellent areas 76c on the back side of the stubs 78 and 79.With this arrangement, each of the label sheets 72 and 73 can be foldedinto two halves along the center line or the boundary line of theadhesive area 75b and the adhesive-repellent area 74c and, at the sametime, only the adhesive slip 76 of the upper label sheet 74 can befolded into two halves along the center line or the boundary line of theadhesive-repellent area 75b and the adhesive area 74b, while only theadhesive slip 77 of the lower label sheet 78 can also be folded into twohalves along the center line or the boundary line of theadhesive-repellent area 75b and the adhesive area 74b.

An overlap type label sheet that comprises only adhesive slips may alsobe realized. An adhesive slip and a corresponding stub may be separatedby means of perforations as described above or, alternatively, by meansof a specifically designed cutting line. Adhesive areas andadhesive-repellent areas may be arranged to form a checkered pattern inplace of a striped pattern as in the case of the above embodiments. Itmay be needless to say an overlap type label sheet according to theinvention may fined applications other than a label for delivery.

Finally, a method of manufacturing a label sheet according to theinvention will be described by way of a roll of label sheets. Although amethod of manufacturing a label sheet according to the invention is notlimited thereto and may be modified appropriately so long as suchmodification meets the requirements of the invention.

Referring to FIG. 18, with a method of manufacturing a label sheetaccording to the invention, a label sheet substrate 84 fed out from asubstrate roll 82 is made to enter a printing unit 81 of an offsetprinting machine, where necessary characters and patterns are printed onthe outer surface 83 of the substrate. Then, the substrate 83 is made toproceed to an adhesive application unit 85, where an acrylic typeadhesive is applied to the entire inner surface of the substrate 84 and,if necessary, the applied adhesive agent is dried to set by anappropriate dryer (not shown).

Then, an adhesive-repellent agent is applied to the printed outersurface of the label sheet substrate in an adhesive-repellentapplication unit 86. An ordinary printing machine such as a resin blocktype printing machine may be used if the adhesive-repellent agent is anink type adhesive-repellent agent. The rate of application of theadhesive-repellent agent is typically between 1 and 5 g/cm². If theoperation of printing characters and patterns is also carried out byusing an ink type adhesive-repellent agent, the above described printingstep may be omitted.

In a subsequent step of drying and setting the applied ink typeadhesive-repellent agent, an ultraviolet-ray-set type repellentoverprint varnish (UP200-trade name: available from T&K TOKA Co., Ltd.)is used in this embodiment so that the ink is dried to set throughultraviolet ray irradiation by means of an ultraviolet ray irradiationunit 87. Then, perforations are formed by means of a perforator 88 toclearly define individual label sheets and then taken up to make afinished roll of label sheets 90.

What is claimed is:
 1. A label sheet comprising:a substrate carrying ona surface thereof an adhesive layer, wherein said adhesive layer isformed only on a limited area of the surface; optionally, said substratecomprising an area where perforations are formed; an adhesive free zonewhich is the remainder of said surface and which zone is selected fromthe group consisting of an area where perforations are formed, and anarea along one or more edges of said substrate, and combinationsthereof; wherein the other surface is used for recording information andcarries an adhesive repellant layer formed by applying an ink basedadhesive repellant agent comprising an adhesive repellant agent and acoloring agent,wherein said ink based adhesive repellant agent is anultraviolet-ray-set repellant overprint varnish comprising between 10and 30% by weight of adhesive repellant agent based on the weight of thevarnish.
 2. A label sheet according to claim 1, wherein said label sheetconstitutes part of a larger label sheet wound in the form of a roll. 3.A label sheet according to claim 1, wherein said adhesive-repellantlayer is used as an information recording layer for recordinginformation by printing said information by use of said ink basedadhesive-repellant agent.
 4. A label sheet according to claim 1, whereinsaid adhesive-repellant layer is adapted to marking by hand and/or bymeans of a stamp.
 5. A label sheet according to claim 4, wherein saidlabel sheet constitutes part of a larger label sheet wound in the formof a roll and the ratio of said label sheet's adhesion force per unitwidth in grams per millimeters required to remove said label sheet froma stainless steel plate and the adhesion force per unit width in gramsper millimeters required to unwind said label sheet from said roll at alow speed is between 1.5 and 8.5.
 6. A label sheet according to claim 1,wherein said adhesive repellant agent is a silicon basedadhesive-repellent agent.
 7. A label sheet according to claim 1, whereinan adhesive-repellant free blank section is formed on theadhesive-repellent layer carrying side of said substrate and an adhesivefree section corresponding to said adhesive-repellant free section isformed on the adhesive layer carrying side of the substrate.
 8. A labelsheet according to claim 7, wherein said label sheet is part of a longerstrip-shaped label sheet wound in the form of a roll and clearly definedby perforations.
 9. A label sheet according to claim 8, wherein saidadhesive-repellent layer includes two sections arranged respectivelyalong the longitudinal edges of the substrate and the adhesive layerincludes either two sections arranged respectively along thecorresponding sections of the adhesive-repellent layer or a number ofspots arranged along said corresponding sections.
 10. A method ofmanufacturing the label sheet according to claim 1, wherein said methodcomprises steps of applying an adhesive agent to a surface of asubstrate so as to form an adhesive layer only on a limited area of thesurface with the remainder of said surface being an adhesive free zone,applying an ink based adhesive-repellant agent on the other surface ofthe substrate, and drying and setting said ink based adhesive-repellantagent so as to form an adhesive repellant layer, wherein said ink basedadhesive-repellant agent is an ultraviolet-ray-set repellant overprintvarnish comprising between 10 and 30% by weight of adhesive repellantagent based on the weight of the varnish.
 11. A method of manufacturinga label sheet according to claim 10, wherein said adhesive repellantlayer is adapted to marking by hand and/or by means of a stamp.
 12. Alabel sheet comprising two component label sheets, each component labelsheet comprising a substrate carrying on a surface thereon an adhesivelayer, wherein said adhesive layer is formed only on a limited area ofeach substrate and an adhesive-repellant agent is applied to theadhesive-free areas on the adhesive layer carrying side of eachsubstrate in such a way that, when each component label sheet isseparated from the other component label sheet and folded into twohalves, the areas carrying the adhesive layer are respectively held incontact with the corresponding areas carrying the adhesive-repellantagent, and that the two component label sheets are put together in sucha way that the areas carrying the adhesive layer of either one of thecomponent label sheets are respectively made to contact with the areascarrying the adhesive-repellant agent of the other component labelsheet, and wherein the adhesive-repellant agent is applied using anink-based adhesive repellant agent comprising a coloring agent andbetween 10% and 30% by weight of the adhesive repellant agent based onthe weight of the ink-based adhesive repellant agent.
 13. A label sheetaccording to claim 12, wherein each of said component label sheetscomprises an adhesive slip separable from a stub by means of a line ofperforations.
 14. A label sheet according to claim 13, wherein the stubof each of the component label sheets is provided only with anadhesive-repellent area on a back thereof.
 15. A label sheet accordingto claim 13, wherein adhesive areas are arranged on a back of theadhesive slip of each of the component label sheets respectively atlocations close to and remote from the corresponding stub.